If you've only got Intel graphics, you can use the even cooler GPU sharing that they've implemented for Xen and KVM: https://01.org/igvt-g
I'm running Windows 7 as a Xen guest using Intel GVT-g on my i3-5005U (2C4T, HD Graphics 5500) for the past week now. I've pinned 2 vcpus each to both Dom0 (Ubuntu 15.04) and DomU and use both simultaneously in a dual monitor setup.
I can't comment about Photoshop or Illustrator as I have no experience using those programs, though I do a fair bit of work with PCB CAD tools: OrCAD, EAGLE. I haven't ran into any major issues thus far. Media playback works fine btw; mpv does not report any skipped frames when playing 1080p webm files downloaded from Youtube with youtube-dl.
I recently switched from OSX to Linux on the new Dell XPS 13 and I'm not sure if I should stay with my current dual boot setup, use a VM or get rid of window completely and invest time in learning Gimp and Scribus as alternatives.